This study will prospectively evaluate the medical, economic, and educational benefits of computer-aided monitoring of two randomly selected groups of postoperative cardiac patients (computer-aided and non-computer-aided) that are subdivided into pediatric and adult ages. Two closed loop computer-aided beds will be installed in the surgical intensive Care Unit at the Hospital of the University of Pennsylvania (HUP). All postoperative cardiac patients will be assigned alternately to either a control (no computer-aided monitoring) or experimental (computer-aided monitoring) group. Before the computer is installed medical criteria for optimal postoperative card and standardized patient management protocols will be developed, a laboratory for non-computer related measurements will be installed and some promising transducers will be evaluated. When the computer is installed both control and experimental groups of patients will be treated according to the same patient management protocols, will have the same monitors, and will be evaluated by the same criteria; however, no computer-derived data will be used in the control group. A total of 400-500 patients will be evaluated annually at the hospital. The study should quantitatively define the medical and manpower benefits of computer-aided monitoring of postoperative cardiac patients.